THE BUILDWORLD RULES LIBRARY · WESTERN AUSTRALIA · EVERY STRUCTURE, REFERENCED

The rules.
All of them.

Carport, shed, garage, patio, sunroom, granny flat, new windows, a new kitchen — even a whole house. Every structure answers to the same short stack of laws, and once you see the pattern, none of it is scary. This page holds the pattern, the full matrix, and the sources: nothing here is our opinion — every statement is pinned to the Act, Regulation, Code or Standard it comes from.

9structure types
3principles explain it all
30primary sources
8Acts & Regulations
9engineering standards
JUL ’26current at 30 July 2026
THE THREE PRINCIPLES THAT EXPLAIN EVERYTHING
1 · The class line
The code sorts structures by risk. Class 10a — carports, sheds, garages, patios: non-habitable, lowest risk, lightest rules.16 Class 1a — anything you live in: sunrooms, granny flats, houses. Cross the habitable line and three things arrive at once: energy-efficiency provisions, builder rules at a lower value threshold, and compulsory insurance in your name. Nothing else about the pathway changes — same permit, same 10-day clock.
NCC PT A6 — BUILDING CLASSIFICATION
2 · Deemed-to-comply
Meet the R-Codes’ deemed-to-comply provisions — setbacks, size, siting — and your project is exempt from planning approval by law.813 This is the single most misunderstood fact in Australian building: it applies to a carport, a patio, a granny flat (any lot size, since April 202412) — and yes, to a whole new house. The council isn’t skipped; the rules were agreed state-wide in advance, and you built inside them.
P&D (LPS) REGS 2015, SCH 2 CL 61A · R-CODES
3 · The value lines
Two dollar figures decide who must build it. $50,000 — below this, Class 10a structures need no registered builder and no owner-builder approval (since 1 July 2026).5 $20,000 — above this, habitable work needs a registered builder (who must insure YOU — home indemnity insurance, in your name, before taking a dollar6) or owner-builder approval.7 Below both lines: no builder rules at all.
BS(R) ACT 2011 · HOME BUILDING CONTRACTS ACT 1991
THE MASTER MATRIX — EVERY STRUCTURE, EVERY RULE
StructurePlanning approval?Building permit?Builder & insurance?
Carport (open)
CLASS 10a		 Exempt if deemed-to-comply — open carports get a concession: half the street setback 810 Yes, over 10 m² — certified application, 10-business-day statutory clock 12 None under $50,000 — build it yourself or use anyone 5 deep page →
design →
Shed / workshop
CLASS 10a		 Exempt if deemed-to-comply 813 Yes over 10 m²; small garden sheds under 10 m² are generally exempt 3 None under $50,000 5 design →
Garage (enclosed)
CLASS 10a		 Exempt if deemed-to-comply — 4.5 m street setback; no carport concession 9 Yes — certified 1 None under $50,000 5 design →
Patio / verandah / alfresco
CLASS 10a		 Exempt if deemed-to-comply 8 Yes over 10 m² — certified 13 None under $50,000 5 design →
Sunroom / garden room
CLASS 1a · HABITABLE		 Exempt if deemed-to-comply as an extension to the house 8 Yes — certified; energy-efficiency provisions apply once it’s habitable 15 Over $20,000: registered builder — who must take out home indemnity insurance in your name — or owner-builder approval 67 design →
Studio / granny flat
CLASS 1a · ANCILLARY ≤70 m²		 Exempt if R-Code compliant — on ANY lot size, since April 2024 1112 Yes — certified 1 Over $20,000: registered builder + insurance, or owner-builder 67 design →
Window replacement
RENOVATION		 None Like-for-like is generally maintenance — no permit; a NEW or enlarged opening is structural work and needs one 3 Safety glazing to AS 1288; windows to AS 2047; bushfire zones need rated glazing 232425 design →
Kitchen / cabinetry
INTERNAL FIT-OUT		 None Joinery itself: no permit. Compliance runs through the trades instead — plumbing, gas and electrical work must be done by licensed trades, who lodge their own certificates of compliance 27 design →
New house
CLASS 1a		 Yes — even a whole house is exempt if it meets the R-Codes deemed-to-comply provisions 813 Yes — certified; 7-star energy provisions; footings to AS 2870 1422 Registered builder + home indemnity insurance, or owner-builder approval 67 coming
HOW ANY STRUCTURE BECOMES “TO CODE” — THE CHAIN IS ALWAYS THE SAME
Building Act 2011 (WA)REQUIRES THE PERMIT 1
Building Regulations 2012ADOPT THE NCC AS THE STANDARD 3
The NCCCLASSIFIES YOUR STRUCTURE · SETS PERFORMANCE 1416
Referenced Standards (Pt A4)AS/NZS 1170.2 · AS 4100 · AS 2870 · MADE LAW BY REFERENCE 17
Your structureTHE LIVE NUMBERS ON YOUR QUOTE
THE HONEST EXCEPTIONS — TRUE FOR EVERY ROW ABOVE

When it isn’t this simple

THE SOURCE REGISTER — THE WHOLE LIBRARY, PINNED

Acts & Regulations

  • [1]
    Building Act 2011 (WA) — building work requires a building permit; certified/uncertified pathways; the role of the building surveyor.
    full text →
  • [2]
    Building Act 2011 (WA), s 23 — a certified application must be decided within 10 business days; an uncertified one within 25.
    s 23 →
  • [3]
    Building Regulations 2012 (WA), Sch 4 — work that needs no permit: small freestanding Class 10a structures, and renovations that don’t affect structural soundness.
    Sch 4 →
  • [4]
    Building Services (Registration) Act 2011 (WA) — the builder-registration framework.
    explainer →
  • [5]
    WA Government reform, effective 1 July 2026 — builder-registration threshold for Class 10a sheds, garages and carports lifted from $20,000 to $50,000.
    announcement →
  • [6]
    Home Building Contracts Act 1991 (WA) — home indemnity insurance — a builder doing residential work over $20,000 must insure YOU, in your name, before taking money or starting work.
    fact sheet →
  • [7]
    Owner-builder approval (WA) — the pathway for owners running their own habitable build over the threshold.
    wa.gov.au →
  • [8]
    Planning and Development (LPS) Regulations 2015 (WA), Sch 2 cl 61 & 61A — works exempt from development approval, including R-Codes deemed-to-comply houses, extensions and outbuildings (heritage excepted).
    clause text →

    • Planning instruments

  • [9]
    State Planning Policy 7.3 — Residential Design Codes Vol 1 — the R-Codes: street setbacks (Table 1), boundary setbacks, garage and carport provisions.
    the code →
  • [10]
    R-Codes cl 5.2.1 C1.2 — the carport concession — an open carport ≤60% of frontage may stand at half the Table 1 street setback.
    worked example →
  • [11]
    R-Codes cl 5.5.1 — ancillary dwellings — granny flats: ≤70 m², on the same lot as a single house.
    council guide →
  • [12]
    R-Codes revision, April 2024 — R-Code-compliant ancillary dwellings exempt from planning approval on lots of any size.
    announcement →
  • [13]
    Deemed-to-comply checks — local-government guidance on the DTC pathway and how compliance is assessed.
    council guidance →

    • The National Construction Code

  • [14]
    NCC — free access — the whole code, free to read on registration.
    ncc.abcb.gov.au →
  • [15]
    NCC 2022 Volume Two — Class 1 and 10 buildings — the housing volume: structure, weatherproofing, energy efficiency for habitable buildings.
    volume two →
  • [16]
    NCC Part A6 — Building classification — Class 10a: “a non-habitable building being a private garage, carport, shed or the like”; Class 1a: dwellings.
    Pt A6 →
  • [17]
    NCC Part A4 — Referenced documents — the mechanism that makes Australian Standards enforceable: standards become code by reference.
    Pt A4 →

    • Engineering standards

  • [18]
    AS/NZS 1170.2 — Wind actions — wind regions, terrain, and the free-roof coefficients that make open canopies uplift-critical.
    standards.org.au →
  • [19]
    AS 4100 — Steel structures — steel member capacity, including lateral-torsional buckling.
    standards.org.au →
  • [20]
    AS 2159 — Piling — deep foundations, including screw piles proof-tested by installation torque.
    standards.org.au →
  • [21]
    AS/NZS 4680 — Hot-dip galvanized coatings — corrosion protection for fabricated steel.
    standards.org.au →
  • [22]
    AS 2870 — Residential slabs and footings — footing design by site soil classification.
    standards.org.au →
  • [23]
    AS 1288 — Glass in buildings — safety glazing: where toughened or laminated glass is mandatory.
    standards.org.au →
  • [24]
    AS 2047 — Windows and external glazed doors — performance of manufactured windows: wind, water, operation.
    standards.org.au →
  • [25]
    AS 3959 — Construction in bushfire-prone areas — BAL ratings and the construction they require, glazing included.
    standards.org.au →
  • [26]
    EN 14509 — Insulated sandwich panels — the test standard behind panel manufacturers’ span and load tables.

    • Official guidance

  • [27]
    Building and Energy (WA) — building or renovating your home — the State regulator’s consumer guidance: permits, surveyors, licensed trades and their certificates of compliance.
    wa.gov.au →
  • [28]
    NCC — accessing referenced standards — how to read the standards the NCC calls up, including Standards Australia’s free view-only Reader Room.
    access guide →
  • [29]
    Granny flats — council worked guidance — a local government’s plain-English application of the ancillary-dwelling rules.
    worked guide →
  • [30]
    Building Act 2011 — official overview — the State’s own summary of how the permit system works.
    overview →

    • Pick a structure. Watch its rules apply to your block — live.

    Open the store →

    This library is general information for Western Australia, current at 30 July 2026, and is not legal advice. Legislation, the NCC and planning policy change, and local planning schemes vary — which is why every project’s exact pathway (R-code, heritage status, bushfire mapping, easements, wind region, soil class) is verified against your title and your shire’s scheme as the first step of every order, before anything is made.